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Posted by on in Data Center

20141130-fig01I recently got the chance to revisit the topic of filtering HSRP traffic between datacenters. It was in the initial stages of setup for testing a LISP VM Mobility scenario -- but that's a topic for a later blog. The big picture for this blog: Data Center Interconnect (DCI), filtering HSRP between datacenters as part of optimal forwarding. This topic is also known as "DCI FHRP Isolation". Along the way, I and those working with me found a couple of surprises. I'd like to share those with you. 

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One of my customers asked for helping troubleshooting a port-channel between a HP-UX server and a Cisco Nexus 7000. I did not know much about HP-UX server configuration, but I agreed to take a look at it.
Key take-away: Server terminology does not always match networking terminology.

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It was great to have the chance to attend the September 4, 2014 UCS GrandSlam event / launch with Tech Field Day. One indicator of the importance of the announcements was the copious e-press coverage before and after. There were several announcements at the launch, so I'm planning to discuss the launch one component at a time, work priorities permitting, in a series of blogs.

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I just received an email about ONUG Fall early registration, which ends September 5 (9/5/2014). The incentive is 25% off the regular price. Heads up if you're interested -- time to get moving! By the way, the email mentioned the 25% discount. The page in the above URL is just a gateway page for you to log in or register and create a log in.  You can then register for the event. 

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In case you hadn't noticed yet, Cisco plans a big UCS related announcement for September 4 in New York City. They're calling it the "UCS Grand Slam".

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Posted by on in Wireless

I'd like to tell you a little story about something that came up recently when troubleshooting Wireless (WLAN) multicast ("IPmc"). I ran into something that was a bit unexpected ... maybe obvious to some readers, but nothing I'd ever heard about. Perhaps because sites really doing multicast video are somewhat thin in numbers, and those doing it over wireless even more so? 

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One of my customers is using MPLS VPNs from his service provider to support two separate divisions at his site. We implemented VRFSs (virtual routing and forwarding instances) on his edge MPLS router and on his core Nexus 7K to provide two separate routing instances. This article compares some of the NX-OS VRF command syntax with IOS VRF command syntax.

Key take-away: NX-OS is pretty consistent in just appending "VRF RED" to show the vrf RED routing instance version of most IP commands. IOS has multiple permutations.

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Edited by Marilyn Outerbridge

A very cheap and effective way to perform rudimentary packet-header capturing in IOS is to use the log/log-input keyword at the end of an ACE. This is very easily done. This blog will use the following simple topology for the demonstrations.

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20140516-ONUGI recently had the pleasure of attending the Open Networking User Group (ONUG) conference in New York City. See also http://opennetworkingusergroup.com. My thanks go to Tech Field Day for getting me there and providing some very interesting vendor discussions. The Tech Field Day website has a page dedicated to ONUG, where you can find links to blogs posted by the other attendees. I won't repeat all those links here. 

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A blog I wrote was recently posted on blogs.cisco.com. It is about how appropriate design can prepare for automation -- and that the lesson from automation is that we should be using "cookie cutter" standard designs, where each remote site or office is not a one-off design.

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Posted by on in Software Defined Network

On Sunday afternoon 5/4/2014 I'll be heading to New York City. I'll be joining some of the Tech Field Day bloggers extraordinaire on Monday and Tuesday 5/5-6/2014, for Tech Field Day at ONUG 2014 (Open Networking User Group, NYC, 2014). 

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One of my customers is planning to migrate his data center network to Rapid Spanning Tree. Although RSTP is a well established technology, it will be new to his site. Cisco has a migration discussion here: Spanning Tree from PVST+ to Rapid-PVST Migration Configuration Example

Building on that discussion, I wanted to gather some metrics for him. What would be the impact of moving the access switches first, then the core switches?

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Cisco has courage. The world of IT is changing, and rather than cling to the successes of the past, Cisco is trying to embrace and shape the future.  Bruce Klein quoted Peter Drucker as saying "The best way to predict the future is to create the future." It’s clear that Cisco is trying to do just that.  In order to pull it off, Cisco and its partners will have to change more in the next year than they have in the previous three years. John Chambers says that at least 1/3 of companies will not survive 25 years.

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Posted by on in Data Center

Recently, Cisco generously provided a briefing to the CiscoChampions, updating the group with new details about Cisco ACI. The presentation was NDA until April 2, I presume coordinated with announcements to be made at InterOp. The biggest new item I noticed was OpFlex. I'll tell you what I know about OpFlex below, somewhat below the tantalizing diagram. I'll be posting this quickly in the morning, then off to various tasks. When I can, I'll look at any announcements and apply corrections if necessary. 

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Looking Ahead to the Cisco Partner Summit 2014!

The Cisco Partner Summit 2014 is almost upon us, and I’m looking forward to a great week there.  Cisco has consistently strong events, ones that are worth making the time to participate in.  I haven’t heard numbers, but I have the impression that the in-person event is shrinking in favor of virtual attendance.  If you have the chance to go in person, you should take it, but I encourage anyone at a Cisco Partner who wants to see the future to join us by using the Cisco Virtual Partner Summit 2014.

Here’s what I’m looking forward to:

Tagged in: ciscops14

I'm speaking at both Enterprise Connect and Interop again this year. The Enterprise Connect conference is March 17 - 20, 2014. I'll be presenting the very successful session titled How to Keep Video from Blowing Up Your Network. This session has been well attended and has received very good reviews at past conferences. In it, I discuss the sources of video traffic, their characteristics, and how to identify video traffic on the network. There are some pragmatic mechanisms that can be employed to reduce the amount of work that is needed to identify video traffic. I will then discuss how to handle traffic that you do want, such a a CEO's video conference, and video that you don't want, like video movie downloads or streaming video. There are two approaches to handling video that you don't want and I discuss both, with an example that we have deployed with customers.

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Posted by on in Data Center

20140307-fig01Here in the Baltimore-DC area, we can't wait for Spring to end all the cold snowy weather we've been having. We don't quite see the signs yet. We need a new groundhog! Anybody want a used one?

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Posted by on in Data Center

20140305-nexus9000Ever since I heard that the Nexus 9K has 50% less code, I've been wondering what features were removed from the code. So I did my best to figure it out, since I haven't seen a detailed features list from Cisco yet (early days and all that). I've also noticed that in general the Nexus team historically has put out long lists of supported features, leaving me thinking "yes, that's great -- but what is NOT on the list?" Anyway, the primary focus here will be what features the N9K supports today. We'll get to that after a motivational detour (or some might say "pre-ramble"). 

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Posted by on in Data Center

20140304-fig01The Cisco announcement last November of Insieme ACI and Nexus 9K hardware gave us a plethora of choices, and left many wonder what Nexus box they should use, and where. It behooves us all to understand the Cisco Nexus product positioning, since they aren't cheap, and we don't want to paint ourselves into a corner with the wrong purchase. That's particularly important for consultants and Cisco resellers providing purchasing recommendations. This blog lays out the major considerations in picking which Nexus platform to buy, and where to use it in your datacenter. 

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20140303-fig01I get the strangest looks when I talk about POAP and ask people "Why Aren't You Using It?" Admittedly, it doesn't help that I like to pronounce acronyms like words, and POAP comes out sounding like "Pope" or perhaps "Poe-App". Perhaps it will help if I mention that POAP is the Nexus equivalent of Auto-Install for Cisco routers. I suspect that aside from not being aware of POAP, a lot of people haven't looked into what POAP can do for them. As with Auto-Install, you might have looked and found that it seemed complex. Yes, it's easy enough to paste in the configuration from the CLI, one less thing to troubleshoot. 

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